The planned research is an interdisciplinary longitudinal study of the etiology of alcoholism focused on factors that precede its development. The study may be formally described as a replicated, cross sectional, multiple cohort study. From the general New Jersey population a random sample of 5250 subjects will be enlisted, of whom 2700 will be aged 13 years when first seen and the rest aged 16, 19, 22 and 25 years. Data will be gathered from four general areas: physiology-biochemistry, perception-cognition, personality-behavior, and sociology. Scientists from these disciplinary areas and from life-span development psychology and statistics will collaborate in the program. The subjects will be examined periodically, by scheduled interview, by projective, cognitive-perceptual, personality, autonomic responsivity, and biochemical tests when first enlisted, again at 3-year intervals until age 25, and then at 6-year intervals. Contact will be maintained with subjects several times a year to minimize sample attrition. Information will also be gathered from collaterals by interview and from public record sources. The drinking histories of the subjects, also the use of other drugs, compiled systematically over time, will be analytically compared repeatedly with biological, psychological sociocultural variables recorded in the successive examinations, and with the occurrence of alcohol-related and other problems. Analyses of these relationships will elucidate the specific and interactive factors that precede the emergence of problems and that are significant for the development drinking and the etiology of alcoholism.